Fig. 1.

Cross-reactive binding of SARS-CoV-2 antibodies to HIV-1 glycoproteins. A (I and II) & B. In ELISA and Western blot research, polyclonal antibodies from spike immunised mouse sera were examined for cross-reactive binding to gp140 protein (from clade C J41 foldon & clade B JRFL foldon). The sera collected from N protein (SARS-CoV-2) immunized mice and pre-immune sera was included here as assay negative control. The immunoblot and ELISA experiments were repeated a minimum of 3 times. Data is presented as the mean ± SD, and differences between groups were determined by two-way analysis of variance (ANOVA) followed by Tukey’s post hoc tests using GraphPad Prism 7. Statistical significance between the control and different groups is shown as *P < 0.05, **P < 0.01, ***P < 0.0001, ****P < 0.0001 and ns (non-significant).